Thermal Energy Regulation with 3D Printed Polymer-Phase Change Material Composites

Phase change materials (PCMs) are an attractive option to passively control building heating and cooling. We present a facile method to produce and print PCM-filled inks by a direct ink writing (DIW) technique that leverages spherical PCM particles as viscosity modifiers in a matrix of photocurable resin. We successfully print inks with up to 63 wt% PCM, which have excellent thermal regulation capacity and nearly no leakage over 200 melting/solidifying cycles. A hollow house printed with PCM-filled ink maintained a 40% lower temperature than the external environment when heated. PCMs with different melting points can be simultaneously integrated into resin and printed without detriment to the structure or integrity. Our approach uses PCM particles as both viscosity modifiers for 3DP and passive thermal management to produce effective thermal buffers and is compatible with a wide range of photopolymer matrices and PCMs, without requiring prior microencapsulation of the PCMs.